A Contrast Experiment on the Ventilation Direction towards Human Head in Personalized Environmental Control System (PECS)

Abstract

A heating, ventilation, and air-conditioning system is designed for the entire space but falls short in meeting diverse individual needs. Therefore, the personalized environmental control system is proposed to address individual thermal requirements and it has been widely accepted and produced to have significant practical value for humans. In order to enhance the comfort level based on the PECS, the impact of the airflow direction towards the head in terms of physiological and psychological sensations was investigated. Different airflow directions were considered as follows: front blowing (FB-PV), side blowing (SB-PV), back blowing (BB-PV), top blowing (TB-PV), and a control group No-PV. A total of 56 participants were invited to assess the thermal environment, and their skin temperature was measured. The results revealed that the airflow towards the head improved thermal comfort and reduced the mean skin temperature by 0.4–0.6 °C, with FB-PV showing particularly promising results. TB-PV demonstrated the highest level of comfort with a score of +1.05 (slightly higher than “Just comfortable (+1)”) and scored significantly higher in overall willingness at +1.21 (higher than “Willing (+1)”). Conversely, FB-PV resulted in a discomfort level due to restricted breathing under the continuous airflow condition.